


A First Time is Always Nerve Wracking

by Gemonie03



Category: Shall We Date?: Obey Me!
Genre: Blow Jobs, F/M, Face-Sitting, First Time, Heavy Set MC, Lingerie, Vaginal Sex
Language: English
Status: Completed
Published: 2020-03-31
Updated: 2020-03-31
Packaged: 2021-03-01 05:34:49
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,048
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/23409775
Author URL: https://archiveofourown.org/users/Gemonie03/pseuds/Gemonie03
Summary: Mammon and Plus Size!MC's first time. Really it's just porn without plot.
Relationships: Main Character/Mammon (Shall We Date?: Obey Me!), Mammon (Shall We Date?: Obey Me!)/Reader
Comments: 6
Kudos: 227





	A First Time is Always Nerve Wracking

Mammon is so, so nervous. He can practically feel the anticipation hum under his skin. He keeps telling himself that this is  _ stupid _ . You’re just a human! There’s nothing to be nervous about! He’s done this with  _ lots _ of other demons so it should be a piece of cake to do it with a human! Humans probably don’t even expect that much! It’s not like a succubus or incubus that needs to go round after round for food! So  _ why _ is his heart beating out of his chest and his anxiety acting up so bad?

Oh yeah.

Because it’s  _ you _ . You are  _ his _ human. The being that means more to him than money.  _ Money _ ! You  _ might _ even mean more to him than Goldie! That’s a terrifying thought for him…

Terrifying or not tonight is  _ the night _ ! The two of you planned this so thoroughly that Lucifer was starting to get suspicious. The oldest brother had even pinned Mammon into a corner to try and get out of him just  _ what _ exactly it was that the two of you were doing. Mammon is pretty sure his whole face turned bright red as he tried his best to get out of that horrifying situation. The  _ last _ thing Mammon needed right now was for Lucifer to find out about your guys' plans for this evening. He could only imagine the kind of scolding or lecture he would receive… Hell, Lucifer might even hang him up in the stairwell for defiling the exchange student. The idea sent shivers down his spine and not in a fun way.

Tonight  _ had _ to be the night because it was the only night in the foreseeable future that everyone, even Levi, had something else going on and if this turned out to be a disaster then the two of you could hide awkwardly in your separate rooms and then never speak of it again. However, if things went well then… A good shiver went down Mammon’s spine. He certainly hoped things went well. 

He was prepared. He had everything you might need; condoms, lube (though he’s pretty confident you  _ won’t _ need it), candles, clean sheets. Hell, he’d even cleaned his pigsty of a room just for you. Now all he needed was for you to show up after everyone else was gone. The waiting was going to kill him. 

********************

An excited shiver runs through you as you examine the new lingerie you bought. It’s so pretty and lacey! You couldn’t believe that you had found something so perfect, and in your size, at Majolish! Asmo had been curious about just  _ why _ exactly you were searching for sexy underthings, but had accepted your excuse that you “just wanted to feel pretty.” At least, he seemed to accept it, though the look he gave you as he left the house earlier was very, very  _ knowing _ . 

Oh well, so what if he  _ suspected _ something. It didn’t  _ really _ matter. After all, you and Mammon had been dating for months now. You had figured that the others had all assumed that the two of you were sleeping together already. Especially since Mammon spent more nights in your room than his own anyway. 

You weren’t exactly sure why Mammon wanted to treat this so secretively. It was actually making you feel a little bad about yourself. You know you’re a big girl, you’ve always been a big girl, and, up until now, Mammon has never seemed to care. He’s a little tsundere and he obviously has a huge ego, but he’s never made you feel bad about yourself, but now… 

You shake the feeling off. There’s probably a Mammon style reason for all the secrecy, and why he didn’t want you saying anything to anyone. It’s probably not a  _ good _ reason, but it probably makes sense in his head. You only just wish he would have filled you in, because Lucifer had been  _ pissed _ when you refused to tell him what was going on. You were actually worried he might hurt you (accidently) or Mammon (purposely) in his quest to find out what the hell you two were planning. After all, your guys’ track record isn’t great when it comes to secret plans. 

The only person you really wish you could have told was Asmo. He’s the only one of your Devildom friends that you think you could have asked for advice about this situation from. You have no idea what sex with a demon is like. Hell, you don’t even know if demons have the - ehem- same equipment as humans. You  _ assume _ things are at least basically the same. After all, you know that incubi and succubi feed off of human sex, and you have seen a couple of the brothers mostly naked (Asmo has no shame, and you lived with Beel for a week) in human form. They looked the same then, but. . . when sexually aroused to the point of intercourse do they maintain human form or do they go demony?

What did Lucifer say about demon forms? They’re triggered, unwillingly, by extreme emotions or physical stress. Which means that, if Mammon is being Mammon then maybe… Oh man. Sex with demon Mammon. The idea makes your cheeks burn in embarrassment, but you definitely are NOT opposed to the idea. 

You shake your head. Focus. You have to get dressed. 

"MC?" 

You're just pulling on your t-shirt as Beel peeks his head into your room.

"Yeah?" You ask as you take one last look at your makeup in the mirror.

"Are you  _ sure _ you don't want to come with Belphie and me to the Avenue of Silence Sweets Extravaganza? All the shops are going to have free samples and if you get 20 stamps on your card you get a free dessert from Madam Devian's."

“I’m sure,” you smile as you turn to face him.

You’re a little surprised to see him frowning. 

“What’s wrong, Beel?”

“Your clothes look like you’re just planning to sit around, but your face looks like you’re going out. Is Mammon up to something shady again?”

“Uh,” you look at him a little surprised, “I don’t know how you came to that conclusion just from my appearance, but no, Mammon is not doing anything shady… That  _ I _ know of anyway. We’re just going to have a nice night in. Is the makeup too much?”

“No, you look very nice.”

“Thank you.”

“If anything bad happens you know you can always summon me.”

“I know.”

“And Belphie too.”

“I know,” you say again as you take his hand. “Look, Beel, I know that you guys don’t have a lot of faith in Mammon and that he’s done some sketchy stuff in the past, but I love him and I know he loves me too. Even if he has a hard time saying it. I guess what I’m trying to say is that, just this once, please trust your older brother.”

“I don’t think I can trust him, but I do trust you.”

You smile at him.

“Well, I guess that’s about all I can really hope for at this point!” you laugh. 

Beel nods before he turns and leaves your room, shutting the door softly behind him. 

You sigh. Now all you have to do is make sure everyone else is gone. 

You peek out your door and take in the empty hallway. Then you step out and head down to the next door. You knock. No answer. You skip Mammon’s room, but knock on all the other doors. It seems that you have the place to yourself. Perfect. You head back down to Mammon’s room and knock on his door. You barely have time to think before the door opens, just a crack, and then you’re being pulled in. 

He instantly turns away from you and pushes up his sunglasses.

“So, you made sure everyone is gone?”

“Of course.”

“Great! So, uh, welcome?”

“Mammon…”

“I, uh, I got stuff, so, uh you should be happy that The GREAT Mammon was willing to go get all the embarrassing things so that  _ you _ wouldn’t have to!”

“Mammon.”

“AND I cleaned my room! See how nice it is? You should really consider praising The GREAT Mammon!”

“MAMMON!”

He flinches at your raised voice, but  _ finally _ turns to face you. There’s already a blush rising to his cheeks, made all that more noticeable by his lack of sunglasses, but the moment he sees you he turns red from the tips of his ears down to his neck. 

“Thank you for preparing so thoroughly for our evening. I appreciate it,” you start as you move closer to him and take his hands in yours. “I, um, do have to ask though… What’s with all the secrecy? I mean, it’s not like I’m going to go running through the halls blasting “I Just Had Sex” by Lonely Island, but, like, is it something to do with, well, me or…”

“Huh?” Mammon’s brow furrows. “What are you talking about?”

“Well… the GREAT Mammon sleeping with a human, and a, um, heavy set one at that could hurt your carefully cultivated image, right?”

Mammon cocks an eyebrow at you before pulling you roughly into his chest. 

“D-don’t be stupid. I-I-I, uh, I thought that if no one, ya know, knew, then if things don’t go well, we could just pretend it never happened, right? Plausible deniability?”

You snort despite yourself. 

“What!?”

“Where did you learn the phrase ‘plausible deniability’?”

“S-shaddup! I know stuff!”

“I’m joking! And, I’m glad that the reason was something stupid and not something, um, body related.”

“N-never, y-you’re perfect,” he little more than murmurs into your hair. 

You can’t help, but smile at that as you snuggle a little more firmly into his chest. The two of you stay this way for a long while. Holding each other while he pets your hair and lets his heart rate slow. It’s nice. It’s warm, and loving, and soothing to both of your frazzled nerves. But it’s getting you nowhere. 

You push away from him, much to his confusion, and physically turn him to face away from you. You take a deep breath and then take off the oversized t-shirt and yoga pants you had donned to walk through the halls earlier. You wish he had a mirror nearby, but the closest one is in his closet. Oh well, you know that the gold and white lace babydoll and matching stockings, thong and garter belt look good damn good. Every curve is accentuated, your ample bosom is practically in your face, your hair is perfectly coiffed, and your makeup is natural and not overdone. You know you look like a million bucks and if  _ that  _ doesn’t get the Avatar of Greed going then you don’t know what will. 

You tap on his shoulder. He spins around and instantly his face burns bright red as his eyes go wide.

“M-MC, holy, I mean, uh, fuck! Uh, wow, uh, MC you look, wow. O-of course you look great! You’re in THE Mammon’s colors after all! Ha!”

You roll your eyes.

“I’m glad you like it. I, uh, got it just for you.”

“R-really?”

“Of course! Though I think Asmo was a little suspicious at the color,” you laugh as you play with a bit of lace. 

“Wait!” Mammon grabs your shoulders a little roughly. “You didn’t let that bastard see you like this did you!?!”

You grab his hands.

“No, of course not!” You laugh as you reassure him. “He walked into Majolish as the sales demon was ringing me up. He tried to convince me to model it for him, but I made my excuses and bribed him with dress shopping next week. You are the  _ only _ demon who gets to see me like this. Promise.”

You can almost see when his brain stops working. 

“Mammon?”

“Hm?”

You lean in, taking his face in your hands, and kiss him deeply. It takes him less than a heartbeat to kiss back. He wraps his arms around you, pulls you tightly to him, and buries a hand in your hair. He kisses like his sin; devouring and greedy like Beel scarfing down a 10 course meal. 

You hardly notice as he starts maneuvering the two of you back to his bed. When your legs hit the edge of the bed it startles you and you fall back against the soft sheets. You turn and crawl up bed to lay seductively on your side, but you can’t help but laugh a little as you watch Mammon strip quicker than you’ve ever seen him do anything before. You barely even have time to take a breath before he’s in his boxer briefs and pinning you to the bed. 

He nips and sucks at your neck as he moves down, licking at your collar bones before burying his face in your breasts… where he stays.

“Uh, Mammon?”

He mumbles against your flesh.

“What?”

He lifts his head and gasps for air. 

“I want to die here,” he groans as he collapses completely on top of you.

You laugh as you pet his hair.

“Okay, but I,” you flip your position, “have a better idea.”

You give him a smirk as you kiss and lick down his chest and abdomen. He squirms and moans at every touch to his flesh and you can’t help but revel in every noise. When you get to the band of his underwear you hesitate. 

“Yo, what’s up?”

You snap to attention at the sound of his voice. He already looks a mess. Hair ruffled, flushed from his face to his chest. You smirk again as you nuzzle your nose against his clothed length. He’s already more than half hard and as you mouth at him through the fabric you can feel him twitch against your tongue. He lifts his hips as you pull down his boxers and he moans when his length springs free from the confines. 

As you toss the fabric behind you, you note that he’s not only well groomed, but well endowed. Both are pleasant surprises. You nuzzle against the base of his shaft, before licking and mouthing up the length of him. Every noise that falls from his lips is more than enough encouragement to continue. Once you reach the ruddy head you swirl your tongue, lapping up the bead of precum forming at the slit, before wrapping your lips around him and sliding down as far as you can. 

“F-fuck, M-MC, fuck,” he groans as he burries his hand in your hair.

He doesn’t press or force your movement, just simply grips into your hair. You come back up his length before swirling your tongue over the head and hollowing your cheeks as you slide back down. You set a rhythm as curse after curse spills from his lips. 

“MC, fuck, I’m gonna, fuck, don’t stop, please, fuuuck.”

You double down, picking up speed, and just as you feel him tense, you take him down as far as you can. He comes with a roar, his grip tightening almost painfully as his whole body curls around your head. You swallow what you can as you pull yourself off him. 

A dribble of cum rolls down the corner of your mouth and down your neck. Mammon is on you in less than a second, lapping up the dribble and licking into your mouth to taste himself. His tongue twines with yours as his hands slide the straps of your lingerie down your shoulders just enough for your breasts to free themselves from their confines. He breaks the kiss to ogle the new flesh presented to him.

You’re a little nervous exposing more of your skin to him. You have scars and stretch marks and imperfections that you know for a fact that demons definitely don’t have. And the intensity of his gaze is a little disconcerting. 

“Um, Mammon, you’re kinda staring…”

“They’re magnificent! I mean, I knew they were, ya know, but they’re even better than I thought! Damn MC!”

Well that’s a boost of confidence. 

“Uh, MC, can we take this off?” He asks as he tugs at the babydoll. 

You nod slowly as you release the bra clasps and pull the whole thing over your head. Your arms instantly wrap around your middle, covering your belly. 

“Don’t do that!” Mammon exclaims as he grabs your wrists and pulls your arms away from yourself. “I wanna see.”

You can feel your cheeks burn as his gaze takes in your figure. You can’t make eye contact with him and your nerves are telling you to get up and run. Just when you think you can’t take his gaze any longer his lips are on yours and his hands are cupping your breasts. Suddenly he shifts and drags you on top of him. 

“MC, uh, so, I was thinkin’ you could, uh, I-I want you to, uh, s-sit on my f-face.”

You’re definitely surprised to hear that. You’ve never done that before and frankly you’re worried he really will suffocate. 

“I-I don’t know if that’s a good idea…”

“Why?” He asks as he gives you an incredulous look.

“W-well… I’m kinda… big and I don’t want to hurt you…”

“Pffffft,” he looks at you like you’re crazy, “I’m a demon. It’s gonna take more than that to do me in. ‘Sides, I wanna , and if The Great Mammon wants somethin’ he’s gonna get it!”

You can’t help but smile a bit at that. You tamp down your nerves and sit up to properly straddle him. You crawl up the bed, but stop just short of his face. He rolls his eyes before gripping under your knees and dragging you the rest of the way. 

He nuzzles his nose against your clothed folds, sending a shiver up your spine. He laps and sucks at your already soaked panties, teasing you through the lace, and making you squirm. 

“M-mammon, stop t-teasing,” you moan.

He makes a noise in between a growl and a moan before sliding your panties to the side. He circles your clit with his tongue, the new sensation drawing a groan from the back of your throat. As he increases the pressure you subconsciously grind against his face. He groans at the action, encouraging your movements by gripping into your ass and pulling you closer. He slowly slides one finger into you causing you to moan loudly and throw your head back. You grip firmly into his hair, much to his pleasure. 

“O-oh, M-Mammon, yes, you’re such a good boy, Mammon!” you moan as you grind more firmly against his willing tongue.

He whines at the compliment and humps against the air. You can feel his excitement shudder through his body. He slides a second finger into you and increases the pace of his ministrations. 

“Mammon! Ah, Mammon, please, I-I’m gonna!”

Suddenly he flexes his fingers just right to stroke the perfect spot and you come, hard, white spots blurring your vision as wave and wave of pleasure surge through your trembling body. 

He strokes you through your orgasm until it’s almost too much, and just as you think you can’t possibly take anymore he releases you and lets you flop over to the side. Your breathing is ragged and your legs ache as you stretch them out, but it’s been a long time since you’ve had an orgasm  _ that good. _

You barely have any time to breathe before Mammon is hovering over you. You can feel him slide one hand up your stocking covered thigh before he unclips your garters. He makes quick work of the stockings and slides your panties down over your hips. You’re far too blissed out to worry about your insecurities as his hands caress every bit of skin he can.

“Mmm.. MC,” he groans as he licks and nips at your neck, “please can we…”

You nod quickly.

He gives you his trademark rakesh smirk as he grabs a condom and tears it open to roll down his length. He kisses you passionately as he settles between your thighs. He lifts one of your legs into the crook of his arm and presses forward testing your flexibility. You can feel the head of his arousal rub against your folds and the excitement and anticipation send a shiver through you. You grab his face and give him one last passionate kiss as he presses into you. 

The feeling of him filling you is almost too much, too fast, the stretch burns and forces you to break the kiss. His forehead rests against yours as he finally bottoms out. You practically share a breath as you both pant at the feeling of it all. 

You look up at him, his face flush, hair a mess, his eyes screwed shut in pleasure. You can’t help but feel a surge of pride at the thought that  _ you _ did this to him. And then an idea hits you.

“M-Mammon, p-please, b-be a good boy and move,” you sigh as you press kisses all over his face. 

He groans as he pulls back before pressing forward again. He sets a slow pace at first, grinding his pelvis against your clit every time he pushes back into you. The feeling is delicious and sends shocks of pleasure through your core, but soon the pace isn’t enough, you need more. 

“Mammon,” you groan, “h-harder!”

He picks up his pace, slamming into you, hitting your most sensitive spots with every thrust. 

“Ah! Good! Good boy Mammon! Ah! Yes! Yes! Please, Mammon!”

He growls, pace punishing and nearly painful, but so, so good.

You slip your hand between your bodies and rub quick circles against your clit. Electricity surges through you, your every nerve humming as your second orgasm of the night rips through you. 

Mammon groans as your walls tighten around him and his pace gets erratic.

“MC, I-I’m gonna…”

You pull him down for a fervent, sloppy kiss as his hips slam against you one final time. 

“Fffuuuuck.” he groans as he meets his own end.

He collapses against you, breathing ragged, and pinning you to the bed. You nuzzle against his ear and gently stroke his hair as both of your breathing returns to normal. He stirs after a moment and rolls over with a groan, sprawling out beside you. 

“That, that was…”

“Great,” you giggle as you curl up against his side, hand draping over his chest. 

“Of course it was! I’m The Great Mammon after all!”

You huff a laugh as you snuggle closer to him. 

“What time is it?” you ask lazily.

“Uh, clock says 9.”

“Can I stay here tonight?”

“Only if I can be the li’l spoon.”

“Mmmm…”

The two of you shift to move blankets and get comfortable. Mammon reaches over and turns off the lights before you wrap him tightly in your arms. Only moments later do you hear him start snoring peacefully as you too drift off into a deep slumber. 

  
  


***********

Levi frowns as he shuts your door behind him. 

“What’s wrong?” Beel asks, arms full of sweets, Belphie, asleep, riding piggyback. 

“MC isn’t in her room. I got her an autograph, like I promised, but she’s not here.”

“Really? It’s kind of late. Where do you think she went?” Beel asks as he gently sets Belphie down in front of their bedroom door. 

“I don’t know… You don’t think something bad happened to her, do you?”

Beel’s brow furrows. 

Just then Asmo stomps up the stairs muttering to himself, holding his heels in one hand and his jacket in the other. His makeup is smeared and there’s an odd pinkish stain on his white shirt. He nearly bowls Beel over as he makes his way down the hall.

“What are you two doing? You’re in my way!” Asmo snips.

“MC isn’t in her room,” Beel responds, ignoring Asmo’s obviously bad mood.

“Of courses she’s not! At least  _ someone _ in this house is getting laid!” Asmo yells as he slams the door to his room.

Beel and Levi share a look before their faces both light up in a blush. Neither says another word as Levi stalks off to his room and Beel picks Belphie back up and gets them both through their door.

Breakfast was certainly going to be interesting. 


End file.
